Gates in irrigation structures are the main components deals with the water control, and discharge measuring. Nowadays, with the national and international increase, and interest with the problems of water shortage, and how to optimize and save the available quantities of the water, investigators and researchers must give a special care to such components extremely affecting the water saving and control.
The present study is a trial to reach the most suitable angle of curvature of the widely used curved gates, for permitting the discharge, with maximum discharge coefficient.
The experimental work was carried out in the irrigation and hydraulic laboratory of the Civil department, Faculty of Engineering, Assiut University, using seven types of curved gates having a curvature angle of 30, 45, 60, 75, 90, 105, and120 degrees, in addition to the vertical one, using discharge ranging from 5 - 45 l/sec.
Since the discharge coefficient under the study depends mainly on the Reynolds, Froude numbers, gate opening and angle of curvature, Such parameters had been studied for all the above mentioned angle of curvature, and concluded that the curved gate with angle of curvature = 900 gives the maximum discharge coefficient for all the used discharges.